Add basic support for SwiftUI views

MMMTestCase.podspec

@@ -1,20 +1,21 @@
 #
 # MMMTestCase. Part of MMMTemple.
-# Copyright (C) 2015-2022 MediaMonks. All rights reserved.
+# Copyright (C) 2015-2024 MediaMonks. All rights reserved.
 #
 
 Pod::Spec.new do |s|
 
 	s.name = "MMMTestCase"
-	s.version = "1.9.0"
+	s.version = "1.10.0"
 	s.summary = "Our helpers for FBTestCase and XCTestCase"
 	s.description = s.summary
 	s.homepage = "https://github.com/mediamonks/#{s.name}"
 	s.license = "MIT"
 	s.authors = "MediaMonks"
 	s.source = { :git => "https://github.com/mediamonks/#{s.name}.git", :tag => s.version.to_s }
 
-	s.platform = :ios, '11.0'
+	s.platform = :ios, '15.0'
+	s.swift_versions = '5.0'
 
 	s.framework = 'XCTest'
 	s.dependency 'FBSnapshotTestCase/Core'

Sources/MMMTestCase/MMMTestCase.swift

@@ -5,6 +5,7 @@
 
 import Foundation
 import MMMCommonCore
+import SwiftUI
 import UIKit
 
 #if SWIFT_PACKAGE
@@ -45,7 +46,7 @@ public enum MMMTestCaseSize {
 				return NSValue(cgSize: CGSize(width: width, height: height))
 		}
 	}
-};
+}
 
 extension MMMTestCase {
 
@@ -86,7 +87,73 @@ extension MMMTestCase {
 			identifier: identifier,
 			backgroundColor: backgroundColor
 		)
+	}
+
+	private class WrapperController: UIViewController {
 
+		private let viewController: UIViewController
+
+		public init(_ viewController: UIViewController) {
+			self.viewController = viewController
+			super.init(nibName: nil, bundle: nil)
+			addChild(viewController)
+			viewController.didMove(toParent: self)
+		}
+
+		public required init?(coder: NSCoder) { fatalError() }
+
+		public var fitSize: CGSize = .init(width: 320, height: 480)
+
+		public private(set) lazy var container = MMMTestCaseContainer()
+
+		override func viewDidLoad() {
+			super.viewDidLoad()
+			view.addSubview(container)
+		}
+
+		override func viewWillLayoutSubviews() {
+			super.viewWillLayoutSubviews()
+			container.setChildView(viewController.view, size: fitSize)
+			let bounds = view.bounds.inset(by: view.safeAreaInsets)
+			container.frame = .init(origin: bounds.origin, size: container.sizeThatFits(.zero))
+		}
+	}
+
+	private func sizeForFit(_ fit: MMMTestCaseSize) -> CGSize {
+		switch fit {
+		case .natural: return self.fitSize(forPresetFit: .natural)
+		case .screenWidth: return self.fitSize(forPresetFit: .screenWidth)
+		case .screenWidthTableHeight: return self.fitSize(forPresetFit: .screenWidthTableHeight)
+		case let .size(width, height): return .init(width: width, height: height)
+		}
+	}
+
+	public func verify<T: SwiftUI.View>(view: T, fit: MMMTestCaseSize = .screenWidthTableHeight, identifier: String = "", backgroundColor: UIColor? = nil) {
+
+		let window = UIWindow()
+		let viewController = UIHostingController(rootView: view)
+		let wrapper = WrapperController(viewController)
+
+		window.rootViewController = wrapper
+		window.windowLevel = .normal - 1 // It could be fun to watch snapshots, but let's keep older behavior.
+		window.isHidden = false
+
+		let fitSize = sizeForFit(fit)
+		wrapper.fitSize = viewController.sizeThatFits(in: fitSize)
+		window.setNeedsLayout()
+		// We need the layout to happen naturally now.
+		pumpRunLoopABit()
+
+		self.verifyView(
+			wrapper.container,
+			identifier: [
+				identifier,
+				fitSize.width > 0 ? String(format: "w%.f", fitSize.width) : nil,
+				fitSize.height > 0 ? String(format: "h%.f", fitSize.height) : nil
+			].compactMap { $0 }.joined(separator: "_"),
+			suffixes: self.referenceFolderSuffixes(),
+			tolerance: 0.05
+		)
 	}
 
 	/// Helps generating parameter dictionaries suitable for `varyParameters` from enums supporting `CaseIterable`.

Sources/MMMTestCaseObjC/MMMTestCase.h

@@ -145,6 +145,9 @@ typedef void (^RandomOrderBlock)();
  */
 - (void)flushMainQueue;
 
+/// Pumps all events ready right now unless there are too many that we don't have time left.
+- (void)pumpRunLoopABit;
+
 @end
 
 /**
@@ -180,4 +183,19 @@ NS_SWIFT_NAME(MMMTestCase.TableViewCellWrapper)
 
 @end
 
+/**
+ */
+@interface MMMTestCaseContainer : UIView
+
+@property (nonatomic, readwrite) CGRect testViewAlignmentRect;
+
+- (id)init NS_DESIGNATED_INITIALIZER;
+
+- (id)initWithCoder:(NSCoder *)aDecoder NS_UNAVAILABLE;
+- (id)initWithFrame:(CGRect)frame NS_UNAVAILABLE;
+
+- (void)setChildView:(UIView *)childView size:(CGSize)size;
+
+@end
+
 NS_ASSUME_NONNULL_END

Sources/MMMTestCaseObjC/MMMTestCase.m

@@ -118,19 +118,6 @@ - (NSString *)identifierForValueWithIndex:(NSInteger)index {
 
 @end
 
-/**
- */
-@interface MMMTestCaseContainer : UIView
-
-@property (nonatomic, readwrite) CGRect testViewAlignmentRect;
-
-- (id)init NS_DESIGNATED_INITIALIZER;
-
-- (id)initWithCoder:(NSCoder *)aDecoder NS_UNAVAILABLE;
-- (id)initWithFrame:(CGRect)frame NS_UNAVAILABLE;
-
-@end
-
 @implementation MMMTestCaseContainer {
 	UIView *_autoLayoutContainer;
 	UIView *_childView;
@@ -266,7 +253,7 @@ - (void)drawRect:(CGRect)rect {
 	CGFloat halfLineWidth = .5;
 
 	//
-	// Safety area backtround.
+	// Safety area background.
 	//
 	[[self safetyAreaColor] setFill];
 	CGContextFillRect(c, b);
@@ -278,7 +265,7 @@ - (void)drawRect:(CGRect)rect {
 	CGContextFillRect(c, [self safetyBounds]);
 
 	//
-	// Guidlines corresponding to the alignment rectangle.
+	// Guidelines corresponding to the alignment rectangle.
 	//
 	{
 		CGRect r = [_childView alignmentRectForFrame:[self safetyBounds]];